As advances are made in the medical field, surgical procedures requiring precise positioning of monitoring and surgical tools become necessary. For example, radiologists perform numerous percutaneous guided biopsies using ultrasound and computer aided tomography ("CAT") scanning techniques, magnetic resonance imaging techniques and fluoroscopic imaging techniques. Biopsies and other percutaneous procedures are performed using a variety of needle-like instruments. It would be advantageous to stabilize such instruments or at least be able to manipulate them in a more precise manner than with manual operation.
For example, one currently widely applied and popular method for the treatment of prostate cancer is the percutaneous transperineal implantation of radioactive seeds of either Iodine-125 or Palladium-103. This procedure is performed with the patient in the lithotomy position, using an ultrasound imaging probe placed in the rectum to monitor seed placement. A template arrangement which is kept in precise linear orientation with the ultrasound probe must be accurately oriented adjacent to the perineum in relation to the prostate, and locked in position throughout the procedure to achieve optimum seed placement. Precise and reproducible orientation of the ultrasound imaging probe in the rectum is the key element in both the calculations required for determining the number and distribution of radioactive seeds required for treatment and their subsequent placement using pre-loaded needles guided by the perineal template and real time ultrasound imaging. This form of treatment for prostate cancer has been increasing in popularity because of minimal patient morbidity compared to other available treatments and the potential for improved efficacy due to increasingly accurate methods of seed placement.
Presently, there are many homemade and commercially available devices for holding, manipulating and stabilizing the various commercially available ultrasound imaging probes designed for use in this procedure. None of these devices have achieved wide acclaim because of significant limitations in their ease of use. In general, these devices suffer from the same basic limitation in that they are "post-insertion" probe fixation devices where the probe is first inserted into the rectum and then affixed to a stand. This inevitably leads to a reorientation of the probe, vis-a-vis the insertion cavity, and valuable time is wasted in recreating mechanically the desired probe orientation that was readily achieved with the freedom of omni-directional manual movement.
In an attempt to remedy these shortcomings, certain "pre-insertion" fixation devices have been developed. In these devices, the probe is first affixed to a stand and then the combination of the fine adjustment mechanism with the probe affixed is released to the free "omni-directional" mode to enhance insertion of the probe into the body of the patient. For prostate cancer treatment, for example, the probe is manually inserted into the rectum and, once the desired orientation is achieved as viewed and confirmed by the monitored ultrasound images, the device is then "set" in the "fixed" mode.
Many currently available devices provide multi-axis movement, but movement in one or more of these axes is clumsy, inaccurate and risks significant loss of orientation in other axes during adjustment, or control of the fine adjustment is severely limited. Moreover, such current devices are cumbersome and tend to either be heavy and/or broad-based to achieve floor stand based stability or spatially cumbersome table-mounted structures which tend to obstruct the surgeon's movements and patient access.
Several presently available examples of post-insertion cumbersome devices for prostate treatment are available in the marketplace. One such device is available from Seed Plan Pro of Seattle, Wash. called the Northwest Transperineal Prostate Implant Stabilization Device. Another such currently marketed device very similar thereto is offered by Hutchinson Medical Designs. A third similar immobilization device offered by Mick Radio-Nuclear Instruments, Inc. of Bronx, N.Y. is called the Cotan Stabilizing Device. Mick also distributes the Martin Immobilization Device which can be used as a "pre-insertion" fixation device but has no fine adjustment mechanism for positioning after insertion. Thus, there remains a need for improved holding, manipulation and stabilizing devices for use in this procedure. In addition, there are numerous other medical procedures where enhanced holding, manipulation and/or stabilizing devices can be helpful.